If your being cheap with food there are 3 roads you can take. Soups, Breads, or Chili. All three things are cheap, make large amounts, and keep for a reasonably well amount of time assuming you store it correctly. Chili is pretty straight forward... Soups are as well I personally like French Onion Soup, it sounds fancy it taste fancy but it's a pretty simple respire... Then there is bread, a 5lb bag of flour will make you about 7-9 loafs of bread that will be fairly large in size assuming you make about 8 loafs with the 5lbs of flour, aside for that you'll need salt, yeast, and water and with that you can make most of your traditional basic breads such as french breads, baguettes, etc. (Self employed and owner of a bakery in town)